Robert r



om 9 m 6 e n u l d e t n e t a P N. o S ,m B o R.. u". Dn. am 4 2, 6 2 6 0. N

GUIDE SUPPORT FUR CDMPASSES.

(Appumion mea Feb. 1s, 189s.)

(No Model.)

INI/EN TOH TTOHNEYJ MZ if/Maw nms ums co. wmoumo.. wgsmuomm n c.

W/TNESS (j/@ 2, MW

we Nu PATENT ROBERT R. ROBINSON, OF NEWV YORK, N. Y.

GUIDE-SUPPORT FOR COMPASSES.

SPECIFICATION forming part of Letters Patent No. 626,246, dated J une 6, 1899.

' Application filed February 18, 1898. Serial No. 670,786. (No model.)

To all whom, t may concern/.-

Be it known that I, ROBERT R. ROBINSON, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Guide-Supports for Compasses, of which the following is a full and complete specification, such as will enable those skilled in the art to which appertains to make and use the same.

rlhis invention relates to supporting devices for compasses; and it has for its object to provide a simple and improved device of this character in which a compass may be conveniently clamped, so that in the use of the compass as a marking device at right-angle corners the support will travel against one surface and maintain the compass in true relative position.

The invention is fully disclosed in the following specification, of which the accompanying drawings form a part, in which the separate parts of myimprovement are designated by the same letters of reference in each of the views, and in which- Figure l is a side view of my improved supporting. device, partly in section. Fig. 2 is an edge viewshowing a compass in secured position therein, and Fig. 3 is an end view of the device with the compass in position.

Referring to the drawings, A designates the supporting device, which comprises a base arm or member B, having a flat bottom edge c, which is adapted to bear against and slide upon the wall or surface at right angles to that upon which the compass is used. The base-arm B is provided upon its top with an enlargement ZJ, forming a shoulder e, the face of which shoulder at its outer end is provided with an angular recess, as at f.

G designates a supplementary arm, which is slidably mounted upon the base-arm B and is provided at its inner end with a similar projection or enlargement 7L, forming a shoulder c', in the face of which, at its outer end, is provided an angular recess 7c. The arm G is provided with a longitudinally-arranged slot Z, in which operates aset-screw M,Which enters a threaded opening n in the base-arm B. To provide against lateral displacement or strain in the sliding operation of the arm G upon the base-arm B, the latter may be provided with a longitudinal rib, as at o, extending from its shoulder e to the opposite endof the arm, and the bottom face of the arm Gr is provided with a corresponding longitudinal groove or channel p.

The operation and advantages of my invention will be readily understood by those skilled in the art to which it appertains. The arm G may be slidably adjusted upon the basearm B and secured in adjusted position by means of the set-screw M,the respective shoula ders e and e' of the arms being adapted to abut when the limit of adjustment is reached. One arm q of a compass R is adapted to be clamped within and between the recessed outer portions f and 7c of the adjoining projections or enlargements d and 7L upon the respective arms, in which position the compass will project at right angles to the supporting device A. By the adjustment of the supporting device the compass can be readily connected with or detached from the device. Vhen the compass is firmly clamped in the supporting device, the fiat bottom edge or face c of the base-arm B will rest against and travel upon the walls or surface at right angles to the surface upon which the points of the compass are used, thus maintaining the compass in true relative position and insuring accu rate marking. Thus with the compass-arms clamped in the supporting device at right angles thereto the base of the supporting device may be moved along one of the walls or surfaces and the compass-arm marks off a i straight line on the adjoining wall or surface. Ordinarily when compasses are operated simply by hand without a supporting-guide device considerable inaccuracy necessarily ensues.

S designates a set-screw, which may be arranged to operate through the projection or enlargement h of the arm G and bear with relation to the arm of the compass to securely bind the latter in position. i

Having fully described my invention, I claim as new and desire to secure by Letters Patent A supporting device for Compasses, comprising a body portion having a iiat base portion forming a guide-surface, an upwardlyprojecting portion having a vertical plane surface and cutaway in the upper portion thereof IOO ' a set-screw passing through said adjustable member and adapted to bind it in adjusted position, and a set-screw passing through said adjustable member and adapted to bind a compass-arm in said recess of said upwardly- 15 projecting portion, substantially as and for the purpose set forth.

In testimony that I claim the foregoing as my invention I have signed my name, in pres` ence of the subscribing Witnesses, this 16th zo day of February, 1898.

' ROBERT R. ROBINSON.

Witnesses:

L. M. MULLER, V. GILMARTYN. 

